Pre-ignition may occur during an operation of an internal combustion engine. Pre-ignition is a self ignition process of a mixture of gas and/or fuel and air in a combustion chamber of the engine. Pre-ignition may occur at high-engine loads and/or high temperatures. Pre-ignition of the mixture of gas and/or fuel and air may result in very high cylinder pressures and may potentially damage the engine.
U.S. Pat. No. 4,979,481 relates to a control apparatus for an internal combustion engine having cylinders. Each of the cylinders is provided with an exclusive fuel injection valve. Each cylinder has a misfiring detecting means for detecting misfiring in that cylinder. The control apparatus includes a drive stopping means for stopping the driving of the fuel injection valve corresponding to a misfired cylinder so as to stop fuel supply to that misfired cylinder. The apparatus is further provided with an air-to-fuel ratio sensor in the exhaust path of the engine so that when misfiring of the cylinder is detected, the fuel injection valves remain controlled through a feedback control. The openings of the normally fired cylinders are controlled in accordance with the air-to-fuel ratio signal outputted from the air-to-fuel ratio sensor in such a way that the apparent air-to-fuel ratio of the cylinders is given by an equation L=nLo/(n−p) where L is the apparent value of the air-to-fuel ratio of the cylinders when p cylinders are misfired, n is the number of cylinders, Lo is the air-to-fuel ratio of the cylinders when all of the cylinders are normally operating, and p is the number of misfired cylinders.